1. Field of the Invention
This invention relates to plant husbandry and especially to sheet or field planting suitable for urban environments.
In particular, the invention concerns a modular field planting system suitable for a rooftop garden.
2. Description of Related Art
The integration of living plants within an urban environment can provide aesthetic, ecologic and economic benefits. For example, rooftop gardens, also known as green roofs, have been found to reduce air and noise pollution, recycle carbon dioxide, control building heating and cooling costs, absorb roof rain runoff and eliminate water pooling, prolong roof life by avoiding direct exposure to solar energy, and prevent blockage of roof drainage systems by trapping debris. Furthermore, roof top vegetation can prevent and/or retard the spread of fire through the roof structure. Additionally, rooftop gardens can create new recreational space which is of particular significance within a crowded urban environment.
Rooftop gardens are typically designed by placing a layer of ordinary soil spread onto a roof surface. A distinct problem of this arrangement is that the structural integrity of the roof may be compromised unless the roof is reinforced for the additional deadload. Another shortcoming of rooftop gardens is that the roots from the vegetation can penetrate and damage the roof surface. Furthermore, the roof surface must be adequately waterproofed to prevent leakage as a result of drainage from the overlying soil. The aforementioned rooftop garden systems also require professional installation and maintenance and can present difficulties if there is a need to access the underlying roof surface.
Another more easily maintainable roof gardening arrangement involves freestanding planters, pots and/or containers. However, this arrangement does not readily provide continuous coverage of the roof surface. Rectangular planters may provide improved coverage however a disadvantage of rectangular planters is that the top edges of the several adjacent planters are visible and it does not create the appearance of a unitary field planting. Another problem with growing plants in pots, planters, or containers, is that the restricted space for lateral root spread can result in detrimental loss of nutrients and water necessary to sustain the plants. A further limitation is that planters and the like, placed on a roof surface are subject to over-turning due to wind forces and are particularly unstable on sloped roof surfaces. Another disadvantage of independent planters is that they must be separately watered and with shallow potting systems water retention is of particular concern.
Previous planter devices have attempted to provide a self-contained water source such as disclosed in U.S. Pat. No. 6,357,179. Although the patented device describes a water reservoir, it does not rely upon a wicking medium for delivering constant moisture. Furthermore, the patented concept does not involve an expansive growth pattern as in field planting. The wicking system described in U.S. Pat. No. 4,219,967 is intended for use with a flowerpot or planter and does not contemplate incorporation within a field planting system as in the present invention.